/* FCE Ultra - NES/Famicom Emulator
 *
 * Copyright notice for this file:
 *  Copyright (C) 2002 Xodnizel
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "mapinc.h"

#define r1 mapbyte1[0]
#define r2 mapbyte1[1]

static void DoBS(void) {
	if (r1 & 0x40) {
		ROM_BANK32((r1 & 0xE) | (r2 & 1));
		VROM_BANK8(((r1 & 0xE) << 2) | ((r2 >> 4) & 7));
	}else {
		ROM_BANK32(r1 & 0xF);
		VROM_BANK8(((r1 & 0xF) << 2) | ((r2 >> 4) & 3));
	}
}

static void R1Set(uint8 V) {
	if (r1) return;
	r1 = V;
	MIRROR_SET(V >> 7);
	DoBS();
}

static void R2Set(uint8 V) {
	r2 = V;
	DoBS();
}

DECLFW(R1W) {
	R1Set(V);
}

DECLFR(R1R) {
	uint8 r = CartBR(A);
	R1Set(r);
	return r;
}

DECLFW(R2W) {
	R2Set(V);
}

DECLFR(R2R) {
	uint8 r = CartBR(A);
	R2Set(r);
	return r;
}

static void M15Restore(int version) {
	DoBS();
	MIRROR_SET(r1 >> 7);
}

static void M15Reset(void) {
	r1 = r2 = 0;
	DoBS();
	MIRROR_SET(0);
}

void Mapper234_init(void) {
	SetWriteHandler(0xff80, 0xff9f, R1W);
	SetReadHandler(0xff80, 0xff9f, R1R);

	SetWriteHandler(0xffe8, 0xfff7, R2W);
	SetReadHandler(0xffe8, 0xfff7, R2R);

	SetReadHandler(0x6000, 0x7FFF, 0);
	SetWriteHandler(0x6000, 0x7FFF, 0);

	M15Reset();

	GameStateRestore = M15Restore;
	MapperReset = M15Reset;
}

